Free Trader:
Power plant: 60 power
Basic systems: 20 power
jump Drive: 40 power
Low Births: 2 power
Power Defecit: 2 points when using low births

Yes, I know you can shut down some basic systems when you need extra power, but seriously, will you want to be without your Mr. Coffee for the entire week in jump space?
What if one sleepy morning, someone decides to make toast, killing power to the low births? Oops, I turned on the Nintendo while the dishwasher was still running - sorry for the misjump, guys, but I really needed my FIFA 5628 fix.

BTW: the power requirements area of the common spacecraft chapter does not indicate the power needs of sensors and low births. It really should.

p.144 wrote:Jump Drive: In order to use the jump drive, the ship requires a number of Power points equal to 10% of the hull’s total tonnage multiplied by the maximum jump number the drive is capable of. Note that this power requirement is only needed when the ship actually makes a jump – at all other times, the jump drive remains inert.

...

Jump Drive: The jump drive does not ordinarily drain any power until it is used – however, it is when a crisis has developed that has reduced a ship’s power that the crew usually want to jump, so it will be more common for other systems to be shut down in order to allow the jump drive to function!

Both of these say that the jump drive uses no power until it is used.
Is hurtling thru jump space not using the drive? Maybe p.148 will tell us...

p.148 wrote:To jump, a ship creates a bubble of hyperspace by means of injecting high-energy exotic particles into an artificial singularity...

The page goes on and on about jump-related topics, but I don't see anywhere mentioned that the jump drive is or is not needed while the ship is in jump.

So I think it is a reasonable request to add a clarification. Because without it, or someone pointing out the passage I missed, it is reasonable for one to read it such that the Jump Drive needs to be powered during the entire jump.

It states clearly, and you've underlined it in your quote, that jump drive power is only needed when the ship makes the jump. It also specifically states that at all other times, the jump drive is inert.

That is about as crystal clear as you get. The jump drive is a catapult, not a constant thrust.

Don't worry, no one can say it needs to be powered during the entire jump because that is literally the opposite of what is stated on page 144.

I see where Allanimal is coming from. It's a matter of if the Jump Drive is required to be active to maintain the integrity of the Jump bubble for the duration of the jump.

But as Nerhesi puts it, the rules as written have it set up as the Jump Drive being a Catapult. Once you're in jimpspace, you're in. There's no risk of falling out if someone does something stupid and blows up your drive.

However it is a good point to bring up as I did think of it as needing the drive active for the duration of the jump and killing it mid way would be a way to drop out somewhere along the route.

The ship isn't hurtling through space, unfortunately. It's in jump space, with nearly empty fuel tanks. Some would say the ship is "just coasting along".

allanimal wrote:I think it is a reasonable request to add a clarification. Because without it, or someone pointing out the passage I missed, it is reasonable for one to read it such that the Jump Drive needs to be powered during the entire jump.

Maybe. I've never used Traveller ships the way they are described in the book. Players are not interested in any of the dry stuff anyway. Just as well that "less is more" when describing how jump works. Less to metagame about at the table.

It states clearly, and you've underlined it in your quote, that jump drive power is only needed when the ship makes the jump. It also specifically states that at all other times, the jump drive is inert.

That is about as crystal clear as you get. The jump drive is a catapult, not a constant thrust.

Don't worry, no one can say it needs to be powered during the entire jump because that is literally the opposite of what is stated on page 144.

So it sounds to me like you define "makes a jump" as "initiates a jump" - or turns on the jump drive to enter jump space.

Maybe I missed the definition, but "makes a jump" could also be interpreted, as I have been, as all that, plus the time in jump space and the transition back to real space. The start and finish of the "jump".
Again, is there a definition of this somewhere in the book I am missing?

PsiTraveller wrote:
Even if you want to have the Jump Drive on during the week in space the M-Drive is off and you have the points from that extra, so there is no power deficit.

Not on the Far Trader - unless you think it is realistic to have some "basic systems" powered down for so long.

Even the Free trader will need to power down 1/10th of the basic systems if it is using all its low berths.

Belisknar wrote:But as Nerhesi puts it, the rules as written have it set up as the Jump Drive being a Catapult. Once you're in jimpspace, you're in. There's no risk of falling out if someone does something stupid and blows up your drive.

Where is this stated? I just am not seeing it in the book anywhere, at least in unambiguous terms. I can kind of see it on p144, but I still can read it my way.

allanimal wrote:Maybe I missed the definition, but "makes a jump" could also be interpreted, as I have been, as all that, plus the time in jump space and the transition back to real space. The start and finish of the "jump".
Again, is there a definition of this somewhere in the book I am missing?

It's never been spelled out precisely how jump works. Just like in the novels that Traveller borrows from do not either.

allanimal wrote:

Belisknar wrote:But as Nerhesi puts it, the rules as written have it set up as the Jump Drive being a Catapult. Once you're in jimpspace, you're in. There's no risk of falling out if someone does something stupid and blows up your drive.

Where is this stated? I just am not seeing it in the book anywhere, at least in unambiguous terms. I can kind of see it on p144, but I still can read it my way.

If the bubble pops, you fall out of jump space is all. Look up misjumps.

ShawnDriscoll wrote:
It's never been spelled out precisely how jump works. Just like in the novels that Traveller borrows from do not either.

Exactly.

So, in the rules, can we have an explicit statement whether the jump drive needs power only while entering jump and not during the duration of the jump, or whether it needs power during the entire jump from start to finish?

ShawnDriscoll wrote:
It's never been spelled out precisely how jump works. Just like in the novels that Traveller borrows from do not either.

Exactly.

So, in the rules, can we have an explicit statement whether the jump drive needs power only while entering jump and not during the duration of the jump, or whether it needs power during the entire jump from start to finish?

It's Marc Miller's universe that is licensed here. That's just the way it is. The idea being that you can't get sued later for using an idea from a story in your own RPG if you don't state that idea exactly.

Lots of stuff in Traveller is not detailed out exactly for such reasons. Referees are free to detail out those things for their "In My Traveller Universe..." postings on this forum.

Besides, we don't want every ship in Traveller using the exact same method of star travel. And we don't want every lifeform to know the inner workings of it all. You want there to be passenger players in a game that say in-character to the Captain, "You're telling us that we are out of fuel? How can that be when we are clearly in jump space at the moment?!"

phavoc wrote:Power for the jump drive is only needed at the time of jump. So they have plenty of power to jump OR maneuver. That's the trade off. Which, for the most part should be ok.

Are you saying that the jump drive doesn't need power during the week in jump?
That makes no sense to me.

Yes, that's exactly what I'm saying. Jump drives only are required to get the ship into jump space, after that they have no effective use. Even the ships powerplant only needs to power lifesupport and internal power as the weapons are useless and you cannot use your drive (I suppose you could turn it on, but it would not provide any useful thrust because you couldn't go anywhere).

From page 141 of the 1st edition Core Rulebook:

Jump travel is the only known means by which a vessel may travel faster than the speed of light. To Jump, a ship creates a bubble of hyperspace by means of injecting high-energy exotic particles into an artificial singularity. The singularity is driven out of our universe, creating a tiny parallel universe which is then blown up like a balloon by injecting hydrogen into it. The Jump bubble is folded around the ship, carrying it into the little pocket universe.

This new universe is short-lived, and will eventually collapse, precipitating the ship back into normal space several light-years from its original position.

So ships don't actually "travel" through the standard universe. It's more like you bend the two points of space/time so that they overlap. On one side you pop into jump space and 7 days later you pop out on the other side. And, as was mentioned above, the jump drives only function is to create the jump bubble. It collapses on it's own volition with no additional input required by the jump drive.

There are some articles talking about jump space in other editions, magazines and such. But you are right, the core rulebooks don't go into lots of detail. Then again, I suspect probably half of the buyers of the books are players who have worked with previous editions, so the explanations are already known.

1. You can't drop out of jump space if the power supply is interrupted.

2. You only need that much power for a very small window of time, and you can rig that up with batteries or some other gadget that collects that energy required for a jump six transition from a minimum sized power plant that produces normally just enough energy to keep the life support and the computer running.

phavoc wrote:
From page 141 of the 1st edition Core Rulebook:
...
There are some articles talking about jump space in other editions, magazines and such. But you are right, the core rulebooks don't go into lots of detail. Then again, I suspect probably half of the buyers of the books are players who have worked with previous editions, so the explanations are already known.

1st edition Mongoose (or other editions of traveller, other external sources, etc.) are irrelevant - we're talking about 2nd edition Mongoose core rule book here. One can't be expected to buy other stuff to use the core rules of the game.

Here is some evidence that the jump does include the time spent in jump space, and is not simply the act of transitioning to jump space:

2nd Ed CRB p153 wrote:starships usually make two jumps per month. They spend one week in jump, followed...

The ship is "in jump" during that week.
Show me where the jump drive does not need power during the "in jump" time?

Remember p.144 says:

2nd Ed CRB p144 wrote:Note that this power requirement is only needed when the ship actually makes a jump – at all other times, the jump drive remains inert.

To me, "one week in jump" is part of "makes a jump". Because you can't "make a jump" without spending that "one week in jump" - it's all part of the complete jump process. I can see how one could read "makes a jump" to mean "initiating the jump" (pulling the trigger on the catapult, to use Belisknar's word), but can you not also see how one may interpret it as the entire process of jumping from one place and showing up at another? And if you can see it both ways, can you not agree that adding a couple words to the text to specify which one is intended would be a good thing?

I don't need lots of details about how jump travel works. To be honest, I don't care. I really don't need explanations from other sources - it needs to be in this book. I just need a few more words in what's already there to take away the uncertainty.

Something like:

p144 proposed wrote:Note that this power requirement is only needed when the ship actually initiates a jump – at all other times, including the week spent in jump space, the jump drive remains inert.

Does anyone object to that?

ShawnDriscoll wrote:It's in jump space, with nearly empty fuel tanks.
...
"You're telling us that we are out of fuel? How can that be when we are clearly in jump space at the moment?!"

I'm also not seeing in the CRB 2nd ed where it states all jump fuel is used up the instant jump travel starts... Again, maybe I missed it. Again, if it is important for game play, it needs to be in this book, not in High Guard 2nd edition or any other traveller book ever written (or magazine, or web site, or comment from Marc Miller at some con in Milwaukee in '82.). Not everyone has the same RPG experiences & history (and book collection) as others, especially those new to the game. The info, if it is important and key to the game mechanics, needs to be in this book.

I did a search of the CRB for both "fuel" and "Hydrogen", neither search turned up a reference to all jump fuel being consumed instantaneously. This one doesn't have any major mechanical impact that I can think of, so I don't see an issue, so I won't push for a clarification in this book...